I thought the first part was tchaikovsky's Entey of Romeo from the opera Romeo and Julliet and the second piece from the same opera, maybe even the same as the first piece ?
mata hati - The title theme is "Dance of the Knights" from Prokofiev's ballet "Romeo and Juliet".
EllieTack - Since Dru acts as Music Supervisor, i.e. arranges pieces of commercial music in addition to composing original tracks for the show (including several new ones for series 4), perhaps contacting him directly would be fruitful.